Adaptive temperature reset control of air conditioning to improve on-site photovoltaic self-consumption and self-sufficiency in cooling-dominated buildings

With rapid deployments of photovoltaic (PV) systems, imbalances between energy supply and demand become increasingly pronounced. Air conditioning is a major consumer of electricity and a key energy flexible resource to improve PV onsite consumption. This study developed and evaluated four easy-to-deploy indoor temperature reset strategies for air-conditioning systems, including a time-of-use strategy and three adaptive strategies, based on a building simulation platform of a typical office building in Guangzhou. Results showed that the adaptive indoor temperature setpoint reset strategies effectively alleviated mismatches between PV power and electric load of air-conditioners. The adaptive strategies increased PV self-consumption and self-sufficiency by 5.4%–14.3% and 14.7%–17.7%, respectively, compared to a fixed-setpoint baseline case. The building envelope thermal mass provided inherent storage capacity, allowing load shifting by lowering temperature setpoints in PV-surplus periods and increasing setpoints in PV-deficit periods without compromising thermal comfort. Detailed energy flow analysis of the external wall demonstrated that the adaptive control strategies improved the efficiency of energy storage and release in a range of 5.6%–55.6%, as compared to the baseline. Incorporating fan speed regulation extended the feasible range of temperature setpoint reset, thereby enabling a more effective balance between grid independence and thermal comfort. The economic assessment showed 28.8%–30.7% annual reductions in operational expenditures under the adaptive control strategies. The shortest payback period for the PV-driven air-conditioning system was 5.4 years. The proposed control strategies provide an easy-to-deploy approach to promote solar energy utilization in buildings and to further reduce urban building carbon emissions.